1. Field of the Invention
The present invention relates to a modified extrusion head for use in a crushed ice machine. It includes modified bosses that break rods of ice into smaller pieces of a pre-determined size. Large and small bosses are shaped differently so as to break ice rods up into chunks. The larger bosses flange outward at the top of the extrusion head while the smaller bosses do not extend to the top of the head.
2. Prior Art
Crushed ice is a highly desired commodity especially in the restaurant and convenient store businesses. Large volumes of ice are used daily by both of these industries as well as others. As a result, many different designs have been developed for crushed ice making machines capable of forming crushed ice rapidly and continuously.
U.S. Pat. No. 4,429,551, issued on Feb. 7, 1984 to Hizume discloses an extrusion head for an auger type icemaker whose bosses extend downward over the topmost portion of the auger. The design is intended to prevent choking of crushed ice that is pushed up over the top of the extrusion head. It contemplates the use of standard methods for breaking the ice down into smaller pieces. It does not contemplate modifying the upper end of the bosses to break up the ice without use of additional structural features.
U.S. Pat. No. 4,467,622, issued on Aug. 28, 1984 to Takahashi et al. discloses an extrusion head specifically designed to form shaved ice of superior quality. The channels of the extrusion head formed by its bosses each contain a small slit or channel that allows air to escape from the ice. This prevents excessive cooling of the ice and forms harder shaved ice particles. This patent also contemplates the use of a standard method of breaking the ice bars into shaved ice chips. It does not suggest that changing the shape of the upward end of the bosses may improve the breaking of the ice bars into crushed ice.
U.S. Pat. No. 4,741,173, issued on May 3, 1988 to Neumann discloses an extrusion head having modified fins or bosses designed to prevent the ice column from rotating within the extrusion apparatus. As with the above two patents, it contemplates the use of an angled surface to impinge upon emerging ice bars to break up the ice. While the angled surface shown in this patent is intended to rotate, the mechanism operates in the same manner. It does not suggest the modifications made in the present invention.
U.S. Pat. No. 5,109,679 issued on May 5, 1992 to Hida discloses an auger type ice making machine having multiple blades above the extrusion head for breaking the ice rods into shaved ice pieces. The blades are adjustable so that the size of the shaved ice pieces may be readily adjusted. While this patent does illustrate a new, alternative method of breaking the ice rods into pieces of ice, its method is vastly different than that of the present invention. As with other ice breaking devices, the blades rotate at the same speed as the auger and the size of the ice pieces is adjusted by adjusting the distance between the blades. It does not suggest that modifying the bosses about the extrusion head could create an alternative method of breaking the ice rods.
U.S. Pat. No. 5,197,300 issued on Mar. 30, 1993 to Sakamoto et al. discloses an auger type ice making machine. The patent is apparently developed by Hoshizaki, one of the manufacturers you named for us. The device disclosed in this patent has an extrusion head that bobs, or oscillates, in an up and down motion. It is intended to convey some of the load applied to the extrusion head by the auger to a cam device located above the extrusion head. As with much of the prior art, it contemplates only the use of an annular flange to break the ice rods into smaller pieces of ice.
U.S. Pat. No. 5,460,014 issued on Oct. 24, 1995 to Wang discloses an auger type ice making machine that has a unique auger-within-an-auger design. As with the other patents uncovered in the search, this patent only contemplates the use of an annular flange to break apart the ice rods. The novelty of this patent lies in increasing the efficiency of heat transfer from the water to the FREON coolant.
U.S. Pat. No. 5,911,749 issued on Jun. 15, 1999 to Sugie discloses an auger-type ice maker. This patent is also owned by the Hoshizaki company. The patent discloses a specially designed boss for the formation of ice forming channels about the extrusion head. The lower end of the boss is curved in such a way as to prevent over compression of the ice. This reduces the back load on the auger, thereby increasing efficiency of the machine. It does not disclose any novel methods of breaking the ice rods or ice bars into smaller pieces of ice.
The extrusion head shown in the above patents all divide a tubular sheet of ice into a series of ice rods that are then broken up into smaller pieces of ice by various devices above the extrusion head. Some of these devices are complicated and require multiple moving parts. Other devices are stationary but do not break the ice rods into uniform pieces of crushed ice. Relatively long pieces of the ice rods may remain in tact. This results in an inferior crushed ice product.
It is therefore desirable to provide means of continuously producing crushed ice having a minimum number of moving parts.
It is also desirable to provide a method of continuously producing crushed ice in which the crushed ice pieces are uniform in size.